Colored film forming composition and method of manufacturing colored film coated glass product

ABSTRACT

By using a colored film forming composition, which contains at least an organic silicon compound and chloroauric acid and to which is added at least one type of compound exhibiting the maximum exothermic peak in the range of 170° C. to 250° C., in differential thermal analysis, the precipitation of gold micro-particles on the film surface can be prevented and gold micro-particle dispersion glass can be manufactured in a stable manner. 
     The colored film forming composition of the present invention can thus be used for coating the surface of glass products, especially, windows, mirrors, etc. of automobiles and other vehicles and buildings.

This is the national stage of International Application No.PCT/JP98/01052, filed Mar. 13, 1998.

FIELD OF THE ART

The present invention concerns a colored film forming composition, inparticular a composition of excellent preservation stability for formingcolored films to be used in windows, mirrors, etc. of automobiles andother vehicles and buildings, and a method for manufacturing coloredfilm coated glass products using the colored film forming composition.

BACKGROUND ART

Among methods of obtaining colored glass is the ion exchange method inwhich a glass surface is coated with an inorganic salt of silver or aninorganic salt of copper and then baked to cause the silver or coppermicro-particles in the inorganic salt to permeate into the glasssubstrate and thus cause colloidal coloration of glass to occur. Thereis also a method in which a salt of gold, silver, or other metal isdissolved in a silicon alkoxide solution, the resulting solution iscoated onto the substrate, and heat treatment is performed to form asilicon oxide coating containing metal micro-particles.

In particular, glass which has been colored by the surface plasmon ofgold or silver micro-particles excels in heat and light resistance andhas been used priorly as colored glass or filter glass. In recent years,the sol-gel method has come to be used widely. For example, a method ofproviding a colored film coated glass plate is described in J. Sol-Gel.Sci. Techn. 1, 305-312 (1994) in which a glass substrate is coated witha solution containing chloroauric acid and alkoxide of silane and thensubject to heat treatment to form a silica film as a matrix containinggold micro-particles in the dispersed condition.

However, in obtaining a gold micro-particle dispersion colored filmcoated glass by the sol-gel method, there was a problem in that in theabovementioned process of heat treatment of the film, the growth of goldmicro-particles occurs at the same time as the contraction of the matrixand the gold micro-particles thus tended to become expelled outside ofthe film. Since the expelled gold micro-particles come off readily whenthe film is wiped with the hands, the proportion of chloroauric acid inthe coating solution that remains as gold micro-particles in the coloredfilm is decreased and the coloring effect is weakened. Also in theactual mass production process, the amount of micro-particles that areexpelled outside of the film varies and this has been a factor ofvariation of the quality of colored glass and has lead to a lowering ofyield and increases in cost.

The object of the present invention is to present a colored film formingcomposition, with which the precipitation of gold micro-particles on thefilm surface is prevented and gold micro-particle dispersion glass canbe manufactured in a stable manner by the sol-gel method, and a methodof manufacturing a colored film coated glass product using the coloredfilm forming composition.

DISCLOSURE OF THE INVENTION

The present invention presents in a colored film forming composition,containing at least an organic silicon compound and chloroauric acid, acolored film forming composition characterized by adding at least onetype of compound that exhibits the maximum exothermic peak in the rangeof 170° C. to 250° C., in differential thermal analysis.

In the present invention, an organic compound or an inorganic compoundmay be used as at least one type of compound, with which the maximumexothermic peak is exhibited (the temperature at which the maximum peakamong several exothermic peaks occurs) in the range of 170° C. to 250°C., in differential thermal analysis and which is to be added to thecolored film forming composition containing at least an organic siliconcompound and chloroauric acid. As said organic compound, an organiccompound having one ether bond and a carbon-carbon double bond insidethe molecule can be used favorably. Acrylate, methacrylate, and vinylcompounds can be given as favorable examples of such an added organicsubstance, and trimethylolpropane triacrylate (maximum exothermic peaktemperature=234° C.), having six ethylene oxide units in the molecule,can be given as a specific, preferable example. The amount of saidorganic substance to be added is preferably 0.5 to 5 wt. %, or morepreferably, 0.7 to 4 wt. % of the total amount of the colored filmforming composition (total amount of the coating liquid, including thesolvent). It is presumed that the variation of the amount added withinthese ranges lead to changes in the particle size or particle shape ofthe gold micro-particles, and the transmission color tone of the coloredfilm can be adjusted thereby. When the amount added is too small, thefilm surface precipitation prevention effect is weakened. It is also notpreferable for the amount added to be too large since bright colorationwill not result, and the film will take on a color close to metallicgold, and the haze will be large. This is considered to be due to thesize of the gold micro-particles becoming too large.

Examples of inorganic compounds that exhibit the maximum exothermic peakin the range of 170° C. to 250° C., and in differential thermal analysisinclude cerium nitrate (maximum exothermic peak temperature=200° C.),cobalt chloride (maximum exothermic temperature=234° C.), iron nitrate(maximum exothermic temperature=225° C.), and iron chloride (maximumexothermic temperature=249° C.). The amount of the abovementionedinorganic compound to be added is preferably 0.3 to 20 wt. %, or morepreferably, 0.5 to 15 wt. % of the total amount of solids of the coloredfilm forming composition (total amount of solids after the colored filmforming composition has been dried and baked into a solid film). Sincethese inorganic compounds remain inside the colored film as oxides, whenthe amount used is high, cerium oxide will absorb ultraviolet rays whilecobalt oxide and iron oxide will absorb visible light to change thecolor tone of the colored film.

In the heat treatment process after the coating of the above-describedcomposition onto the substrate surface, the organic silicon compoundundergoes hydrolysis and polycondensation to form a silica matrix andthe chloroauric acid undergoes thermal decomposition to form goldmicro-particles. By the addition of a compound having the maximumexothermic peak in the range of 170° C. to 250°, the goldmicro-particles are prevented from not contributing to coloration bybeing expelled outside of the film and precipitating on the surface ofthe film, and the coloration effect is thus increased. Furthermore,subtle variations of the color tone are enabled by adjusting the amountof said added compound.

The reason as to why the abovementioned added compounds prevent theprecipitation of gold micro-particles on the film surface is presumed tobe as follows. That is, judging from the TG-DTA characteristics curve ofthe abovementioned compounds, the added compounds exhibit the maximumexothermic peak and decreases suddenly in weight at a temperature in therange of 170 to 250° C. In the process of heat treatment of the coatingfilm, the network structure of the silica matrix becomes smaller at atemperature near 200° C. due to rapid contraction of the film. Duringthis process, the gold micro-particles that are in the network structureand are in the growing process tend to be expelled outside of the filmas a result of being expelled outside of said network. However, theadded compound restricts the rapid contraction of the film at this pointand thereby secures a region for growth of the gold micro-particles andprevents the gold micro-particles from becoming expelled outside of thefilm. Also, after the gold micro-particles have grown completely, thecontraction of the matrix will have also progressed and thus the goldmicro-particles will not be expelled outside of the film. Furthermore,due to generation of heat by the added compound, the growth of goldmicro-particles and the contraction of the matrix surrounding the goldmicro-particles occur at the same time with the growth and fixing of thegold micro-particles occurring in a short time. By adjusting the amountof additive, that is, by adjusting the spacial region in which the goldmicro-particles can grow and the amount of heat generated, subtlecontrol of the color tone is enabled. If a compound that exhibits themaximum exothermic peak at a temperature less than 170° C. or more than250° C. is added, since the temperature at which the compound generatesheat will not coincide with the temperature at which the goldmicro-particles are formed and precipitated, the compound will not beable to prevent the expulsion of gold micro-particles outside of thefilm.

The respective components of the above-described colored film formingcomposition of the present invention shall now be described.

The organic silicon compound causes the film to have a silicon oxidecomponent. This silicon oxide component is necessary as a matrixmaterial of low refractive index that fixes the gold micro-particles andcauses the coloration of the gold micro-particles to be reddish. Thesilicon oxide component is also necessary for keeping the visible rayreflectance of the film at a low value. If the content of the siliconoxide component is too low, the reflectance becomes too high. On theother hand, if the content is too high, the coloration becomes weak andthe value of the colored glass as a product is lowered. The content oforganic silicon compound, as weight percentage of SiO₂ in the totalamount of solids of the colored film forming composition, is thuspreferably 50 to 94 wt. %, or more preferably 70 to 92 wt. %

The organic silicon compound, which is to be the raw material of thesilicon oxide that forms the colored film in the present invention, canbe any silicon compound which enables a more transparent and strongerfilm to be formed by the sol-gel method and is excellent in stability,that is, any silicon compound that can undergo hydrolysis andpolycondensation. Specific examples shall be given below.

An alkoxide of silicon is preferable as the organic silicon compound asa raw material for silicon oxide. Tetraalkoxysilanes, such astetramethoxysilane, tetraethoxysilane, tetrapropoxysilane,tetrabutoxysilane, etc. can be given as examples. Condensates (of n≧2,where n indicates the degree of condensation) of the above compounds ormixtures of such condensates may also be used. Condensates that can beused include, for example, hexaethoxydisiloxane (n=2),octaethoxytrisiloxane (n=3), decaethoxytetrasiloxane (n=4),ethoxypolysiloxane (n≧5), etc. Mixtures, such as "Ethyl Silicate 40"(product trade name for the Colcoat Co.), which is comprised of amixture of monomer (n=1) and condensate (n≧2) [the composition in weightpercentage, indicated in J. Cihlar's literature on Colloids and SurfacesA: Physicochem. Eng. Aspects 70 (1993) pp. 253 to 268, is monomer (n=1):12.8 wt. %, dimer (n=2): 10.2 wt. %, trimer (n=3): 12.0 wt. %, tetramer(n=4): 7.0 wt. %, polymer (n≧5): 56.2 wt. %, ethanol: 1.8 wt. %], can beused favorably.

Also, compounds such as alkyltrialkoxysilanes, in which the alkoxy groupof an abovementioned compound is replaced by an alkyl group or otherhydrocarbon group, may also be used. Compounds in which the alkoxy grouphas been replaced by a straight chain or branched alkyl group, such asthe methyl group, ethyl group, propyl group, butyl group, 2-ethylbutylgroup, octyl group, etc., by a cycloalkyl group, such as the cyclopentylgroup, cyclohexyl group, etc., by an alkenyl group, such as the vinylgroup, allyl group, γ-methacryloxypropyl group, γ-acryloxypropyl group,etc., by an aryl group, such as the phenyl group, toluyl group, xylylgroup, etc., by an aralkyl group, such as the benzyl group, phenethylgroup, etc., by the γ-mercaptopropyl group, γ-chloropropyl group,γ-aminopropyl group, etc. can be given as examples.

The chloroauric acid in the above-described colored film formingcomposition of the present invention is for dispersed precipitation ofthe gold micro-particles within the film, and the gold micro-particlesin the film are necessary for coloring the film in a bright color. Ifthe amount of gold micro-particles is too high, not only does thedurability of the film become low, but since the gold micro-particlesare formed after the film is coated due to reasons of manufacture, themicro-particles become large in shape and prevent the desired colorationfrom being obtained. Thus the content of chloroauric acid, as the weightpercentage of Au in the total amount of solids of the colored filmforming composition, is preferably 5 to 20 wt. %, or more preferably 7to 18 wt. %.

Though the colored film forming composition of the present inventionthus contains, in addition to the compound exhibiting the maximumexothermic peak at 170° C. to 250° C. in differential thermal analysis,the organic silicon compound of an amount corresponding to 50 to 94 wt.% SiO₂ in the total amount of solids and chloroauric acid of an amountcorresponding to 5 to 20 wt. % Au in the total amount of solids, thecolored film forming composition may also contain, as necessary, othercomponents including a metal compound such as an organic zirconiumcompound, organic aluminum compound, organic titanium compound, organicor inorganic manganese compound, organic or inorganic chromium compound,organic or inorganic nickel compound, organic or inorganic coppercompound, organic or inorganic zinc compound, organic or inorganicvanadium compound, organic or inorganic indium compound, organic orinorganic bismuth compound, organic or inorganic antimony compound,organic or inorganic tin compound, etc. The above compounds,respectively, cause the colored film to have a zirconium oxidecomponent, an aluminum oxide component, a titanium oxide component, amanganese oxide component, a chromium oxide component, a nickel oxidecomponent, a copper oxide component, a zinc oxide component, a vanadiumoxide component, an indium oxide compound, a bismuth oxide component, anantimony oxide component, and a tin oxide component, and thesecomponents can be contained as necessary for color tone adjustment.However, if the amount of such components becomes too great, thereflectance of the film will become too great. Small quantities oforganic or inorganic boron compound and organic or inorganic phosphoruscompound may also be contained. Thus the total content of metalcompounds, such as organic zirconium compound, organic aluminumcompound, organic titanium compound, organic or inorganic manganesecompound, organic or inorganic chromium compound, organic or inorganicnickel compound, organic or inorganic copper compound, organic orinorganic zinc compound, organic or inorganic vanadium compound, organicor inorganic indium compound, organic or inorganic bismuth compound,organic or inorganic antimony compound, organic or inorganic tincompound, organic or inorganic boron compound, organic or inorganicphosphorus compound, etc., expressed as the total weight percentage ofthe corresponding ZrO₂, Al₂ O₃, TiO₂, MnO₂, Cr₂ O₃, NiO, CuO, ZnO, V₂O₅, In₂ O₃, Bi₂ O₃, Sb₂ O₅, SnO₂, B₂ O₃, and P₂ O₅ in the total amountof solids of the colored film forming composition is preferably 0 to 10wt. %, and more preferably 0 to 8 wt. %.

As the organic zirconium compound to be used as the raw material forzirconium oxide, tetramethoxyzirconium, tetraethoxyzirconium,tetraisopropoxyzirconium, tetra-n-propoxyzirconium,tetraisopropoxyzirconium isopropanol complex, tetraisobutoxyzirconium,tetra-n-butoxyzirconium, tetra-sec-butoxyzirconium,tetra-t-butoxyzirconium, etc., can be used favorably. Zirconiummonochloride trialkoxide, zirconium dichloride dialkoxide and otheralkoxides of halogenated zirconium compounds, in which the alkoxy grouphas replaced by a halogen group, can also be used. Chelated zirconiumalkoxides, obtained by chelation of the abovementioned zirconiumalkoxides with a β-ketoester compound, can also be used favorably.Methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, butylacetoacetate and other acetoacetic acid esters having the generalformula, CH₃ COCH₂ COOR (where R is CH₃, C₂ H₅, C₃ H₇, or C₄ H₉), can begiven as the chelating agent, and among these, alkyl acetoacetates, inparticular, methyl acetoacetate and ethyl acetoacetate are favorable asthese can be obtained at relatively low cost. Although the zirconiumalkoxide may be chelated partially or fully, it is favorable to chelateat a (β-ketoester)/(zirconium alkoxide) molar ratio of 2 since thechelated compound will then be stable. A coating solution cannot beprepared from a zirconium alkoxide that is chelated with acetyl acetoneor other chelating agent other than a β-ketoester compound since thechelated compound will then be insoluble and precipitate in alcohol andother solvents. It is also possible to use alkoxyzirconium organic acidsalts obtained by replacing at least one alkoxy group of anabovementioned zirconium alkoxide with acetic acid, propionic acid,butanoic acid, acrylic acid, methacrylic acid, stearic acid, or otherorganic acid.

Aluminum alkoxides, aluminum nitrate, aluminum chloride, and otherinorganic aluminum compounds and organic aluminum compounds can be usedfavorably as the organic aluminum compound used as the raw material foraluminum oxide.

Titanium alkoxides, titanium acetylacetonates, titanium carboxylates,and other organic titanium compounds can be used favorably as theorganic titanium compound used as the raw material for titanium oxide.Titanium alkoxides are generally expressed as Ti(OR)₄ (where R is analkyl group with up to four carbons), and in view of the reactivity,titanium isopropoxide and titanium butoxide are preferable. In the caseof titanium, it has also been known priorly that the use ofacetylacetonates is preferable due to their stability. In this case, thegeneral formula is Ti(OR)_(m) L_(n) (m+n=4, n≠0), where L indicatesacetyl acetone. Also in this case, a titanium alkoxide may beacetylacetonated using acetyl acetone or a commercially availabletitanium acetylacetonate may be used. Furthermore, carboxylates may alsobe used.

The colored film forming composition of the present invention isobtained by dissolving each of the above raw materials in solvent andmixing the solutions at predetermined ratios. The total amount ofsolvent used is normally 10 to 100 weight parts to 10 weight parts ofthe total of organometallic compound and chloroauric acid. In the casewhere a silicon alkoxide is to be used in the present invention, aninorganic acid, such as hydrochloric acid, nitric acid, sulfuric acid,etc., or an organic acid, such as acetic acid, oxalic acid, formic acid,propionic acid, p-toluenesulfonic acid, etc. is used as the hydrolyticcatalyst.

The solvent to be used in the present invention depends on the filmforming method. For example, an organic solvent of low evaporation rateis preferred as the solvent in the case of the gravure coating method,flexographic printing method, and roll coating method. This is becausewith a solvent of high evaporation rate, the solvent will evaporatebefore adequate leveling occurs. The evaporation rate of a solvent isgenerally expressed by a relative evaporation rate index with that ofbutyl acetate being 100. A solvent for which the value of this index is40 or less is classified as a solvent of extremely low evaporation rateand such a solvent is favorable as the organic solvent for the gravurecoating method, flexographic printing method, and roll coating method.Such solvents include, for example, ethyl cellosolve, butyl cellosolve,cellosolve acetate, diethylene glycol monoethyl ether, hexylene glycol,diethylene glycol, tripropylene glycol, diacetone alcohol,tetrahydrofurfuryl alcohol, etc. It is preferable that the solvent forthe colored film forming composition (coating solution) used in thepresent invention contains at least one of the above types of solvent,and a plurality of the abovementioned solvents may also be used toadjust the viscosity, surface tension, etc. of the coating solution.Also, a solvent, which is high in evaporation rate and has a relativeevaporation rate of over 100, for example, methanol (610), ethanol(340), or n-propanol (300) can be added to the abovementioned solventwith a relative evaporation rate index of 40 or less.

The colored film forming composition of the present invention is coatedonto a substrate by a coating method to be described later andthereafter heated under an oxidizing atmosphere at a temperature of 200to 300° C. for 5 to 200 minutes to cause the gold micro-particles toprecipitate and then baked at a temperature of 500 to 800° C. for 10seconds to 5 minutes to form a thin film of a thickness of 200 nm orless.

A glass substrate can be used favorably as the substrate onto which thecolored film forming composition of the present invention is applied,and as the glass substrate, a glass plate of transparent soda limesilicate glass composition as well as green-colored glass,bronze-colored glass, and glass with ultraviolet ray absorptivity can beused. Since the colored film obtained by the present invention does notprovide a high ultraviolet ray shielding performance by itself, anautomobile glass plate, with a 370 nm wavelength ultraviolet lighttransmittance (T370 nm) of 10 to 50%, a visible ray transmittance of 70to 90%, a solar radiation transmittance of 40 to 85%, and a thickness of1.5 mm to 5.5 mm, is used favorably as the glass substrate. By coatingsuch an ultraviolet ray absorbing glass plate with the colored filmforming composition of the present invention, colored glass of higherultraviolet ray absorptivity can be obtained.

The coating method to be used with the present invention is not limitedin particular and the spin coating method, dip coating method, spraycoating method, printing method, etc. can be given as examples. Printingmethods, such as the gravure coating method, flexographic printingmethod, roll coating method, screen printing method, etc., arepreferable since these are high in productivity and good in theefficient usage of the coating solution components.

The absorption band of surface plasmon absorption, which causes thecoloration of the abovementioned gold micro-particles, shifts accordingto the value of the refractive index of the matrix. The concentration ofthe compound additive, having the maximum exothermic peak in the rangeof 170° C. to 250° C., may also be changed to adjust absorption peak andthe transmission color tone may be adjusted thereby. Thus colored glassproducts, in particular, colored film coated glass plates to be used asautomobile windows, building windows, etc., that are obtained by thecoating and heating of the colored film forming composition of thepresent invention, preferably have a transmission color tone ofchromaticity in the range of a=-4 to 20 and b=-15 to 5, or morepreferably, a=-2 to 15 and b=-12 to 3 in Lab color space. It is alsopreferable for the glass product to have a transmitted light luminosity(L) of 60 to 90.

Since adequate coloration will not be obtained if the thickness of thecolored film obtained by coating and heating the colored film formingcomposition of the present invention is too thin, and the film strengthwill be low and cracking will tend to occur if the film is too thick,the thickness of the colored film is preferably 30 to 200 nm, or morepreferably, 40 to 180 nm, or even more preferably, 50 to 160 nm. Thecolored film has a refractive index of 1.40 to 1.70.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention shall now be described in more detail by way ofspecific embodiments. For optical evaluations of the present invention,optical measurements were made before and after wiping the baked filmsurface with a wiping cloth to evaluate the surface precipitationconditions of the gold micro-particles and thereby clarify the effectsof the invention. In the Tables, Δ Ya indicates the difference (Ya-Y1)between the value of the visible ray transmittance (Ya) after the filmsurface has been wiped (so as to remove the gold micro-particles thatmay have precipitated on the surface) and the value of the visible raytransmittance (Y1) prior to wiping the film surface. The smaller thevalue of Δ Ya, the smaller the amount of gold micro-particles that haveprecipitated on the surface, and thus the greater the effect of thepresent invention.

First Embodiment

6 g of 0.1N hydrochloric acid and 44 g of ethyl cellosolve were added to50 g of ethyl silicate ("Ethyl Silicate 40" made by Colcoat Co., Ltd.)and the mixture was stirred for two hours under room temperature. Theresulting solution was identified as silicon oxide stock solution 1.This contains 20% SiO₂ solids.

A chloroauric acid stock solution was prepared by dissolving chloroauricacid tetrahydrate to a concentration of 10 wt. % in ethyl cellosolve.

5.9 g of ethyl cellosolve and 0.1 g of trimethylolpropane acrylateethylene oxide hexaadduct were added to 2.5 g of the silicon oxide stocksolution 1 that was prepared in the above manner. 1.5 g of thechloroauric acid stock solution were then added and mixing and stirringwere performed to prepare a coating solution 1.

The coating solution 1 prepared in the above manner was then spin coatedfor 15 seconds at a rotation speed of 1000 rpm onto a transparent glasssubstrate (non-colored) of 3.4 mm thickness and dimensions of 10 cm×10cm. After air drying, heat treatment was performed for two hours at 250°C. to precipitate gold micro-particles. The coated glass substrate wasthen baked for 105 seconds at 720° C. to obtain a colored film coatedglass plate. Tables 1 to 3 show the respective characteristics of thecolored film coated glass, that is, the refractive index and filmthickness of the colored film, the visible ray transmittance (Ya), thedifference of visible ray transmittance before and after wiping the filmsurface (Δ Ya), the transmission color tone, the transmissionchromaticity (a, b) and luminosity (L), the visible ray reflectance("glass surface reflectance") and reflection chromaticity•luminosity("glass surface reflection chromaticity•luminosity") measured uponprojection of light from the glass surface side, and the visible rayreflectance ("film surface reflectance") and reflectionchromaticity•luminosity ("film surface reflectionchromaticity•luminosity") measured upon projection of light from thefilm surface side. "E06" indicated in the "Film composition" column ofTable 1 indicates the trimethylolpropane acrylate ethylene oxidehexaadduct and the value thereof (1.0 wt. %) indicates the proportionwith respect to the total amount of coating solution (including thesolvent), and this applies likewise to the second and third embodimentsas well as to the twelfth and thirteenth embodiments (Table 7). Thetrimethylolpropane acrylate ethylene oxide hexaadduct is no longercontained in the baked film. Also in Table 1, the refractive index isthat of the film composition excluding the gold micro-particles (sameapplies to Tables 4 and 7).

The colored film that was obtained showed good results for chemicalresistance and wear resistance. Also, as can be seen from the Table, thefilm exhibited a small Δ Ya of 0.3, which indicates that surfaceprecipitation of gold micro-particles was prevented by the addition oftrimethylolpropane acrylate ethylene oxide hexaadduct as the additive.Surface precipitation of gold micro-particles could not be detected bynaked eye inspection as well.

Second Embodiment

Besides changing the amounts used of ethyl cellosolve andtrimethylolpropane acrylate ethylene oxide hexaadduct, used in preparingcoating solution 1 of the first embodiment, to 5.85 g and 0.15 g,respectively, the same procedures as those of the first embodiment werefollowed to prepare a coating solution 2.

The coating solution that was prepared in the above manner was then spincoated for 10 seconds at a rotation speed of 1000 rpm onto a transparentglass substrate (non-colored) of 3.4 mm thickness and dimensions of 20cm×40 cm. After air drying, heat treatment was performed for two hoursat 250° C. to precipitate gold micro-particles. The coated glasssubstrate was then kept for 120 seconds in an electric oven set to 720°C. and then drawn out and subject to pressing. Immediately thereafter,the glass plate was tempered by air cooling to obtain a curved temperedglass plate with colored film for automobiles. The curved shape was alsoobtained as designed and no transparent distortion was observed.

The visible ray transmittance, visible ray reflectance, transmissioncolor tone, and other characteristics of the colored film are shown inTables 1 through 3. The colored film that was obtained displayed goodresults for chemical resistance and wear resistance.

Also, as can be seen from the Table, the colored film exhibited a smallΔ Ya of 0.13, which indicates that surface precipitation of goldmicro-particles was prevented by the addition of trimethylolpropaneacrylate ethylene oxide hexaadduct as the additive. Surfaceprecipitation of gold micro-particles could not be detected by naked eyeinspection, as well. In comparison to the first embodiment, thetransmission color tone of the present embodiment was shifted towardsthe blue side, and this was considered to be due to a change in theparticle size or particle shape of the gold micro-particles.

Third Embodiment

Besides changing the amounts used of ethyl cellosolve andtrimethylolpropane acrylate ethylene oxide hexaadduct, used in preparingcoating solution 1 of the first embodiment, to 5.80 g and 0.20 g,respectively, the same procedures as those of the first embodiment werefollowed to prepare a coating solution 3.

The coating solution 3 prepared in the above manner and the same type ofsubstrate as that of the first embodiment were used and treatments werecarried out under the same coating conditions and heating/bakingconditions as those of the first embodiment to obtain a glass plate withcolored film. The optical characteristics measured for the firstembodiment were then measured under the same conditions. The results areshown in Tables 1 through 3. The colored film that was obtaineddisplayed good results for chemical resistance and wear resistance. Thesurface precipitation of gold micro-particles was prevented by theaddition of the additive and surface precipitation of goldmicro-particles could not be detected by naked eye inspection, etc. Incomparison to the first embodiment, the transmission color tone of thepresent embodiment was shifted towards the blue side, and this wasconsidered to be due to a change in the particle size or particle shapeof the gold micro-particles.

Fourth to Sixth Embodiment

<Preparation of Coating Solutions 4 to 6>

2 moles of acetylacetone were added by dripping with a drip funnel to 1mole of titanium isopropoxide while stirring. The resulting solution wasused as the titanium oxide stock solution. This contains TiO₂ solids of16.5%.

1.99 g of silicon oxide stock solution 1 were mixed with 0.25 g of thetitanium oxide stock solution and 0.26 g of cerium oxide stock solution,and 5.50 g of ethyl cellosolve were added to the mixture. 2.0 g ofchloroauric acid stock solution were then added and mixing and stirringwere performed to prepare coating solution 4 (fourth embodiment).

Ethyl cellosolve was added to cerium nitrate hexahydrate so that theamount of CeO₂ solids were 23.2% and heating and stirring at 90° C. wereperformed to obtain a cerium oxide stock solution.

2.15 g of silicon oxide stock solution 1 were mixed with 0.17 g of thetitanium oxide stock solution and 0.18 g of the cerium oxide stocksolution, and 5.50 g of ethyl cellosolve were added to the mixture. 2.0g of chloroauric acid stock solution were then added and mixing andstirring were performed to prepare coating solution 5 (fifthembodiment).

2.25 g of silicon oxide stock solution 1 were mixed with 0.12 g of thetitanium oxide stock solution and 0.13 g of the cerium oxide stocksolution, and 5.50 g of ethyl cellosolve were added to the mixture. 2.0g of chloroauric acid stock solution were then added and mixing andstirring were performed to prepare coating solution 6 (sixthembodiment).

Each of the coating solutions 4 to 6 prepared in the above manner wasthen spin coated for 15 seconds at a rotation speed of 1000 rpm onto atransparent glass substrate of 3.4 mm thickness and dimensions of 10cm×10 cm. After air drying, heat treatment was performed on each coatedglass substrate for two hours at 250° C. to precipitate goldmicro-particles. The respective coated glass substrates were furthermorebaked for 120 seconds at 720° C. to obtain three types of colored filmcoated glass plates. The colored film coated glass plates obtained usingcoating solutions 4, 5, and 6 were identified as the fourth, fifth, andsixth embodiments, respectively. The visible ray transmittance, visibleray reflectance, transmission color tone, and other characteristics ofthe respective colored film coated glass plates are shown in Tables 1through 3. The colored films that were obtained displayed good resultsfor chemical resistance and wear resistance. Also in all embodiments,surface precipitation of gold micro-particles was prevented by theaddition of cerium nitrate as the additive and surface precipitation ofgold micro-particles could not be detected by naked eye inspection, etc.It was also shown that the CeO₂ equivalent amounts of cerium oxide shownin Table 1 remained in the films as a result of adding cerium nitrate.

Seventh Embodiment

100 g of iron chloride hexahydrate were dissolved in 195.7 g of ethylcellosolve to prepare a 10 wt. % iron oxide stock solution.

2.38 g of silicon oxide stock solution 1 were mixed with 0.23 g of theiron oxide stock solution, and 5.39 g of ethyl cellosolve were added tothe mixture. 2.0 g of chloroauric acid stock solution were then addedand mixing and stirring were performed to prepare coating solution 7.

The coating solution 7 prepared above was then spin coated for 15seconds at a rotation speed of 1000 rpm onto a transparent glasssubstrate of 3.4 mm thickness and dimensions of 10 cm×10 cm. After airdrying, heat treatment was performed on the coated glass substrate fortwo hours at 250° C. to precipitate gold micro-particles. The coatedglass substrate was furthermore baked for 120 seconds at 720° C. toobtain a glass plate with colored film. The visible ray transmittance,visible ray reflectance, transmission color tone, and othercharacteristics of the colored film are shown in Tables 1 through 3. Thecolored film obtained displayed good results for chemical resistance andwear resistance. Also, surface precipitation of gold micro-particles wasprevented by the addition of iron chloride hexahydrate as the additiveand surface precipitation of gold micro-particles could not be detectedby naked eye inspection, etc. As with the eighth and ninth embodiments,it was also shown that the Fe₂ O₃ equivalent amount of iron oxide shownin Table 1 remained in the film as a result of adding iron chloride.

Eighth Embodiment

2.43 g of silicon oxide stock solution 1 were mixed with 0.13 g of theiron oxide stock solution, and 5.44 g of ethyl cellosolve were added tothe mixture. 2.0 g of chloroauric acid stock solution were then addedand mixing and stirring were performed to prepare coating solution 8.

The coating solution 8 that was prepared in the above manner and thesame type of substrate as that of the seventh embodiment were used andtreatments were carried out under the same coating conditions andheating/baking conditions as those of the seventh embodiment to obtain aglass plate with colored film. The visible ray transmittance, visibleray reflectance , transmission color tone, and other characteristics ofthe colored film are shown in Tables 1 through 3. The colored filmobtained displayed good results for chemical resistance and wearresistance. The surface precipitation of gold micro-particles wasprevented by the addition of iron chloride hexahydrate as the additiveand surface precipitation of gold micro-particles could not be detectedby naked eye inspection, etc.

Ninth Embodiment

Coating solution 8, used in the eighth embodiment, was spin coated for10 seconds at a rotation speed of 1000 rpm onto a UV-cutoff green glasssubstrate (visible transmittance Ya=73.1%, solar radiation transmittanceTg=48.9%, visible light reflectance rg=6.6%, transmission color tone:green with transmitted light chromaticity of a=-7.1, b=2.8, L=86 andreflected light chromaticity of a=-1.7, b=-0.1 as chromaticity in Labspace) of 3.4 mm thickness and dimensions of 10 cm×10 cm. After airdrying, heat treatment was performed on the coated glass substrate fortwo hours at 250° C. to precipitate gold micro-particles. The coatedglass substrate was, furthermore, baked for 120 seconds at 720° C. toobtain a glass plate with a colored film. The visible ray transmittance,visible ray reflectance, transmission color tone, and othercharacteristics of the colored film are shown in Tables 1 through 3. Thecolored film obtained displayed good results for chemical resistance andwear resistance. The surface precipitation of gold micro-particles wasprevented by the addition of iron chloride hexahydrate as the additiveand surface precipitation of gold micro-particles could not be detectedby naked eye inspection, etc.

                                      TABLE 1                                     __________________________________________________________________________    Film composition (Wt %)                                                                      Amount of additive                                                            (cerium                                                                           (iron                                                      Embodiment                                                                          Matrix   nitrate)                                                                          chloride) Refractive                                                                         Film                                        No.   SiO.sub.2                                                                        TiO.sub.2                                                                        Au CeO.sub.2                                                                         Fe.sub.2 O.sub.3                                                                   EO6  index                                                                              thickness                                   __________________________________________________________________________    1     87.5                                                                             0.0                                                                              12.5                                                                             --  --   1.0 wt %                                                                           1.46 125 nm                                      2     87.5                                                                             0.0                                                                              12.5                                                                             --  --   1.5 wt %                                                                           1.46 125 nm                                      3     87.5                                                                             0.0                                                                              12.5                                                                             --  --   2.0 wt %                                                                           1.46 127 nm                                      4     67.0                                                                              6.85                                                                            16.0                                                                             10.2                                                                              --   --   1.54 110 nm                                      5     72.1                                                                              4.79                                                                            16.0                                                                             7.1 --   --   1.51 105 nm                                      6     75.7                                                                              3.35                                                                            16.0                                                                             5.0 --   --   1.50 108 nm                                      7     80.1                                                                             0.0                                                                              16.1                                                                             --  3.9  --   1.49  85 nm                                      8     81.7                                                                             0.0                                                                              16.1                                                                             --  2.2  --   1.47  90 nm                                      9     81.7                                                                             0.0                                                                              16.1                                                                             --  2.2  --   1.47  87 nm                                      __________________________________________________________________________

                  TABLE 2                                                         ______________________________________                                                                      Transmission                                    Embodi-                       chromaticity                                                                           Glass surface                          ment   Ya             Transmission                                                                          luminosity                                                                             reflectance                            No.    (%)     ΔYa                                                                            color tone                                                                            (a/b/L)  (%)                                    ______________________________________                                        1      79.9    0.3    wine red                                                                              6.4/-1.6/88.8                                                                          7.98                                   2      78.0     0.13  pink    7.4/-3.3/87.7                                                                          8.08                                   3      76.9     0.24  pink    6.3/-4.1/87.3                                                                          7.96                                   4      74.2    -0.02  pink    6.1/-4.6/85.8                                                                          10.44                                  5      77.4     0.03  pink    5.7/-3.9/87.6                                                                          9.39                                   6      76.7     0.06  pink    6.9/-4.7/87.1                                                                          9.23                                   7      74.1    0.3    pink    8.9/-4.3/85.4                                                                          8.8                                    8      74.0    0.3    pink    9.3/-4.0/85.2                                                                          8.6                                    9      64.3    0.2    neutral gray                                                                          0.1/0.5/80.2                                                                           6.7                                    ______________________________________                                    

                  TABLE 3                                                         ______________________________________                                                  Glass surface          Film surface                                           reflection             reflection                                   Embodi-   chromaticity                                                                             Film surface                                                                              chromaticity                                 ment      luminosity reflectance luminosity                                   No.       (a/b/L)    (%)         (a/b/L)                                      ______________________________________                                        1         0.2/0.3/28.2                                                                             6.88        3.7/-0.7/25.8                                2         -0.4/0.5/28.4                                                                            5.95        5.5/-2.6/23.9                                3         -0.5/0.5/28.2                                                                            5.49        4.9/-4.2/23.2                                4         3.6/1.5/30.7                                                                             10.4        2.5/3.4/31.8                                 5         3.1/1.2/29.4                                                                             9.39        2.6/2.6/30.1                                 6         3.7/1.6/28.6                                                                             9.23        2.3/3.3/29.8                                 7         1.5/1.5/29.3                                                                             7.9         4.7/1.8/27.3                                 8         1.7/1.3/29.0                                                                             7.8         4.4/1.5/27.3                                 9         -0.8/1.0/26.0                                                                            6.2         1.9/1.7/24.6                                 ______________________________________                                    

First Comparison Example

5.5 g of ethyl cellosolve were added to 2.5 g of silicon oxide stocksolution 1 used in the first embodiment. 2 g of chloroauric acid stocksolution were then added and mixing and stirring were performed toprepare a coating solution 9.

Coating, drying, and baking were then performed in the same manner asthe first embodiment to obtain a colored film coated glass. The visibleray transmittance, visible ray reflectance, transmission color tone, andother characteristics of the colored film coated glass are shown inTables 4 through 6. In Table 4, the refractive index is that of the filmcomposition excluding the gold micro-particles. In comparison to systemsin which additive, etc. of the embodiments of the present invention wereadded, the colored film obtained in the present example exhibited alarge Δ Ya of 1.41, clearly indicating that the surface precipitation ofgold micro-particles had increased. Gold micro-particles that hadfloated to the film surface could also be identified by naked eyeobservation.

Second Comparison Example

Besides using 1-ethoxy-2-propanol in place of the ethyl cellosolve,which was used as the solvent in the first comparison example, the sameprocedures as those of the first comparison example were carried out. Incomparison to systems in which additive, etc. of the embodiments of thepresent invention were added, the surface precipitation of goldmicro-particles had clearly increased and gold micro-particles that hadfloated to the film surface could also be identified by naked eyeobservation.

Third Comparison Example

Besides using methyl cellosolve acetate in place of the ethylcellosolve, which was used as the solvent in the first comparisonexample, the same procedures as those of the first comparison examplewere carried out. In comparison to systems in which additive, etc. ofthe embodiments of the present invention were added, the surfaceprecipitation of gold micro-particles had clearly increased and goldmicro-particles that had floated to the film surface could also beidentified by naked eye observation.

                  TABLE 4                                                         ______________________________________                                                  Film                                                                          composition                                                         Comparison  (wt. %)          Refractive                                                                           Film                                      example No. SiO.sub.2                                                                            Au        index  thickness                                 ______________________________________                                        1           84     16        1.46   115 nm                                    2           84     16        1.46   130 nm                                    3           84     16        1.46   120 nm                                    ______________________________________                                    

                  TABLE 5                                                         ______________________________________                                                                      Transmission                                    Comparison                    chromaticity                                                                           Glass surface                          example Ya            Transmission                                                                          luminosity                                                                             reflectance                            No.     (%)    ΔYa                                                                            color tone                                                                            (a/b/L)  (%)                                    ______________________________________                                        1       76.2   1.41   pink    8.2/-2.5/86.5                                                                          7.3                                    2       75.2   0.93   pink    8.9/-2.3/85.9                                                                          7.5                                    3       77.1   1.13   pink    7.0/-1.9/87.5                                                                          7.8                                    ______________________________________                                    

                  TABLE 6                                                         ______________________________________                                                   Glass surface          Film surface                                           reflection             reflection                                  Comparison chromaticity                                                                             Film surface                                                                              chromaticity                                example    luminosity reflectance luminosity                                  No.        (a/b/L)    (%)         (a/b/L)                                     ______________________________________                                        1          1.2/0.9/26.9                                                                             6.8         2.7/0.1/26.8                                2          1.5/1.2/27.3                                                                             6.9         2.5/0.5/25.9                                3          1.0/1.3/28.5                                                                             7.2         2.2/0.8/26.5                                ______________________________________                                    

Tenth and Eleventh Embodiments

<Preparation of Coating Solutions 10 and 11>

10 g of cobalt chloride hexahydrate were dissolved in 40 g of ethylcellosolve to prepare a cobalt oxide stock solution.

4.5 g of 1N hydrochloric acid and 20.5 g of ethyl cellosolve were addedto 25 g of ethyl silicate, and the mixture was stirred for two hoursunder room temperature. 5.85 g of methyltriethoxysilane, 5.14 g of ethylcellosolve, and 0.70 g of 0.1N hydrochloric acid were then added to theabove solution and the mixture was stirred for two hours. The resultingsolution was identified as silicon oxide solution 2. This contains SiO₂solids of 19.4%.

3.5 g of cobalt oxide stock solution and 12.1 g of ethyl cellosolve wereadded to 15.8 g of silicon oxide stock solution 2 prepared in the abovemanner. 10 g of the chloroauric acid stock solution were then added andmixing and stirring were performed to prepare a coating solution 10(tenth embodiment).

3.0 g of cobalt oxide stock solution and 11.5 g of ethyl cellosolve wereadded to 15.5 g of silicon oxide stock solution 2 prepared in the abovemanner. 10 g of the chloroauric acid stock solution were then added andmixing and stirring were performed to prepare a coating solution 11(eleventh embodiment).

<Coating, Heating, and Measurement>

Each of the coating solutions 10 and 11 prepared in the above manner wascoated onto a transparent glass substrate of 3.4 mm thickness anddimensions of 10 cm×10 cm using a gravure coating device. After airdrying, heat treatment was performed on each coated glass substrate fortwo hours at 250° C. to precipitate gold micro-particles. The respectivecoated glass substrates were, furthermore, baked for 130 seconds at 720°C. to obtain glass plates with colored film. The colored film coatedglass plates obtained using coating solutions 10 and 11 were identifiedas the tenth and eleventh embodiments, respectively. The visible raytransmittance, visible ray reflectance, transmission color tone, andother characteristics of the respective colored film coated glass platesare shown in Tables 7 through 9. With both the tenth and eleventhembodiments, the colored films that were obtained displayed good resultsfor chemical resistance and wear resistance. Also, surface precipitationof gold micro-particles was prevented by the addition of cobalt chloridehexahydrate as the additive and surface precipitation of goldmicro-particles could not be detected by naked eye inspection, etc. Theaddition of the cobalt chloride hexahydrate enabled a bluish tint to beadded to the color tone. It was also shown that the CoO equivalentamounts of cobalt oxide shown in Table 7 remained in the films as aresult of adding cobalt chloride.

Twelfth and Thirteenth Embodiments

A transparent glass substrate of 2.1 mm thickness and dimensions of 10cm×10 cm was prepared.

<Preparation of Coating Solutions 12 and 13>

Coating solution 1 used in the first embodiment was used as coatingsolution 12 (twelfth embodiment).

Diacetone alcohol and 0.1 g of trimethylolpropane acrylate ethyleneoxide hexaadduct were added to 2.58 g of silicon oxide stock solution 2prepared in the tenth embodiment. 1.5 g of the chloroauric acid stocksolution were then added and mixing and stirring were performed toprepare a coating solution 13 (thirteenth embodiment).

<Coating, Heating, Processing, and Measurement>

Each of the coating solutions 12 and 13 prepared in the above manner wasthen spin coated separately for 15 seconds at a rotation speed of 1500rpm onto the transparent glass substrate described above. After airdrying, heat treatment was performed on each coated glass substrate fortwo hours at 250° C. to precipitate gold micro-particles. These coatedglass substrates were placed in a heating oven and raised in temperatureto 610° C. within two hours, kept at said temperature for ten minutes,and then cooled naturally to obtain two types of glass plates withcolored film. A polyvinyl butyral intermediate film of 0.8 mm thicknesswas then sandwiched between the abovementioned transparent glass plateand each of the colored film glass plates with the colored film at theinner side, and heating and pressurization were performed for 15 minutesat 250° C. in an autoclave to obtain two types of laminated glass havingcolored film in the middle. The colored film coated laminated glassplates obtained using coating solutions 12 and 13 were identified as thetwelfth and thirteenth embodiments, respectively. The visible raytransmittance, visible ray reflectance, transmission color tone, andother characteristics of the respective colored film coated laminatedglass plates are shown in Tables 7 through 9. With both the twelfth andthirteenth embodiments, the colored films obtained displayed goodresults for chemical resistance and wear resistance. In the reflectanceand reflection chromaticity columns for "Glass surface" in Tables 8 and9 are shown measured values for light reflected from the entire surfacewhen light is made incident from the external glass surface side of thecolored film coated glass plate between the two surfaces of thelaminated glass, and in the reflectance and reflection chromaticitycolumns for "Film surface" in Tables 8 and 9 are shown measured valuesfor light reflected from the entire surface when light is made incidentfrom the other surface side of the laminated glass plate, in otherwords, from the external glass surface side of the glass plate withoutthe colored film.

                  TABLE 7                                                         ______________________________________                                        Film composition (Wt %)                                                                   Amount of additive                                                Embodi-           (cobalt         Refrac-                                                                             Film                                  ment    Matrix    chloride)       tive  thickness                             No.     SiO.sub.2                                                                            Au     CoO    EO6    index (nm)                                ______________________________________                                        10      83.6   12.9   3.5    --     1.48  120                                 11      81.9   12.9   5.1    --     1.49  120                                 12      87.5   12.5   --     0.1 wt %                                                                             1.46  100                                 13      87.5   12.5   --     0.1 wt %                                                                             1.46  110                                 ______________________________________                                    

                  TABLE 8                                                         ______________________________________                                                                      Transmission                                    Embodi-                       chromaticity                                                                           Glass surface                          ment   Ya             Transmission                                                                          luminosity                                                                             reflectance                            No.    (%)     ΔYa                                                                            color tone                                                                            (a/b/L)  (%)                                    ______________________________________                                        10     68.4    0.1    reddish 7.6/-7.6-82.4                                                                          8.7                                    11     67.0     0.05  purple  8.2/-8.4/81.5                                                                          9.0                                    12     76.9     0.01  reddish 4.5/-1.5/87.9                                                                          7.8                                    13     74.2    -0.03  purple  3.8/-0.8/88.5                                                                          7.5                                                          wine red                                                                      wine red                                                ______________________________________                                    

                  TABLE 9                                                         ______________________________________                                                  Glass surface          Film surface                                           reflection             reflection                                   Embodi-   chromaticity                                                                            Film surface chromaticity                                 ment      luminosity                                                                              reflectance  luminosity                                   No.       (a/b/L)   (%)          (a/b/L)                                      ______________________________________                                        10        3.5/1.3/26.2                                                                            8.6          3.7/1.4/25.8                                 11        4.1/1.3/25.4                                                                            7.6          7.5/1.0/23.9                                 12        0.8/0.6/28.2                                                                            7.9          0.9/0.3/28.2                                 13        0.7/0.5/30.7                                                                            7.5          1.2/0.5/31.8                                 ______________________________________                                    

Effects of the Invention

As has been described above, by the present invention, a minute amountof organic or inorganic additive, having the maximum exothermic peak inthe range of 170° C. to 250° C., is added to a colored film formingcomposition for glass products to enable the generation of goldmicro-particles to be controlled and the precipitation of goldmicro-particles on the colored film surface to be prevented.Furthermore, subtle color tone adjustments are enabled throughadjustment of the amount of additive added.

The colored film forming composition of the present invention can thusbe used for coating the surface of glass products, especially, windows,mirrors, etc. of automobiles and other vehicles and buildings.

What is claimed is:
 1. A colored film forming composition containing atleast an organic silicon compound that can undergo hydrolysis andpolycondensation and at least a chloroauric acid, said colored filmforming composition being characterized in there being added at leastone compound exhibiting the maximum exothermic peak in the range of 170°C. to 250° C., in differential thermal analysis.
 2. A colored filmforming composition as set forth in claim 1, wherein the added compoundis an organic compound having an ether bond and a carbon-carbon doublebond within the molecule.
 3. A colored film forming composition as setforth in claim 2, wherein the added compound comprises 0.5 to 5 wt. % ofthe total amount of the colored film forming composition.
 4. A coloredfilm forming composition as set forth in claim 2 or 3, wherein the addedcompound is a trimethylolpropane triacrylate having six ethylene oxideunits within the molecule.
 5. A colored film forming composition as setforth in claim 1, wherein the added compound is at least one inorganiccompound selected from among a group comprised of cerium nitrate, cobaltchloride, iron nitrate, and iron chloride.
 6. A colored film formingcomposition as set forth in claim 5, wherein the added compoundcomprises 0.3 to 20 wt. % of the total amount of solids of the coloredfilm forming composition.
 7. A method of manufacturing colored filmcoated glass products, characterized in that a colored film formingcomposition, containing at least a silicon containing composition for asol-gel method and at least a chloroauric acid, is coated onto a glasssubstrate and then heated and baked, said method of manufacturingcolored film coated glass products being characterized in that at leastone compound exhibiting the maximum exothermic peak in the range of 170°C. to 250° C., in differential thermal analysis is added to the coloredfilm forming composition.